Device and method for generative production of a three-dimensional object

ABSTRACT

A device and a method for generative manufacture of a three-dimensional object are provided in which 
     a) manufacture of an object, in a construction area of the device, 
     b) removal of the manufactured object from the construction area and 
     c) repeating steps a) and b) are carried out, wherein steps a) to c) are carried out automatically.

The present invention relates to a device and a method for generativemanufacture of a three-dimensional object.

A device for generative manufacture of a three-dimensional object byselective laser sintering is known, for example, from EP 0 734 842 A.There a first layer of a powdered material is applied to a basedetachably connected to a lowerable carrier and irradiated at the pointscorresponding to the object, so the material sinters together there.Then the carrier with the base is lowered and a second layer is appliedto this first layer and again selectively sintered, the second layertherein being connected to the first layer. In this way the object isformed in layers. When the formed three-dimensional object is complete,together with the base it is taken manually out of the device. Thisremoval limits productivity, as during removal no further object can bemanufactured.

The object of the invention is to provide an improved device forgenerative production of a three-dimensional object with whichproductivity can be increased and an improved method for generativeproduction of a three-dimensional object with which productivity can beincreased.

The object is achieved by the device according to claim 1 or the methodaccording to claim 19.

Further developments of the invention a re cited in the sub ordinateclaims.

Further features and advantages of the invention emerge from thedescription of embodiment examples using the figures.

FIG. 1 shows a schematic sectional view of a device for manufacturing athree-dimensional object.

FIG. 2 shows a perspective illustration of the device for manufacturinga three-dimensional object.

FIG. 3 shows a sectional view of a part of the device for manufacturinga three-dimensional object from FIG. 2, in which the construction frameis coupled to the mounting.

FIG. 4 shows the sectional view according to FIG. 3, in which theconstruction frame is uncoupled from the mounting.

FIG. 5 shows the sectional view according to FIG. 3 without constructionframe put in.

FIG. 6 shows an enlarged partial view of region A of FIG. 3.

As can best be seen from FIG. 1, the device for manufacturing athree-dimensional object has a construction frame 1, open to the top andthe bottom, with circular, square or rectangular cross-section with anupper edge 2. In the construction frame a construction platform 3 isprovided, connected to a vertical drive 4. The construction platform 3can be moved up and down in the vertical direction via the verticaldrive 4. On the outer edge of the construction platform 3 a seal 5 isprovided, which seals the gap between the construction platform 3 andthe construction frame 1. Above the upper edge 2 is arranged a hardeningdevice in the form of a laser 6 and a deflection mirror 7. Furtherprovided is another application device 8 for applying the material to beapplied to the construction platform 3. The laser 6, the deflectionmirror 7, the application device 8 and the vertical drive 4 arecontrolled by a control system 9. In the illustration in FIG. 1 a formedobject 10 is drawn in, surrounded by non-hardened material 11. Theconstruction frame 1 and the construction platform 3 together form amobile container 12.

The device shown in FIG. 1 is arranged in a housing 13, shown in FIG. 2.This housing 13 has on its front face a door 14, which opens and closesautomatically. In the housing 13 a construction area is provided, inwhich the object is manufactured. The mobile container 12 is arranged inthis construction area during manufacture. Further provided is a railsystem 15, connected to the housing 13, with a conveyor drive, notshown, e.g. a chain drive. With this rail system 15 an empty mobilecontainer 12 ₁, 12 ₂ is conveyed into the device for manufacturing athree-dimensional object and a full mobile container 12 ₃, in otherwords a mobile container in which a formed object is contained, isconveyed out of the device. For this the rail system 15 has a feedsection 16, a removal section 17 and a connecting section 18, connectedto the device. The feed section 16, the removal section 17 and theconnecting section 18 are connected to one another via switch gear 19.The feed section 16 and the removal section 17 are connected to a store,not shown, in which the empty mobile containers and the full mobilecontainers are kept.

As well as the rail system 15, the device contains a coupling device 20for coupling the mobile container 12 to a mounting 13′ of the housing 13and for uncoupling the mobile container 12 from the mounting 13′. FIG. 3shows a sectional view through the corresponding part of the mounting13′ of the housing 13, wherein a state is shown in which the mobilecontainer 12 is coupled to the mounting 13′. As shown in FIG. 3, theconstruction frame 1 has in each case a projection 21, 22, projectingoutwards at its lower end on both sides. On each of these projections21, 22 an adjustable positioning element 23, 24 is provided in eachcase. The positioning elements 23, 24 also have in each case the effectof a stop. The length of the adjustable positioning elements 23, 24 canbe set in the direction of the movement of the vertical drive 4. Themounting 13′ has abutment faces 25, 26, with which the adjustablepositioning elements 23, 24 are in contact in the coupled state of themobile container 12. As can best be seen in FIG. 4, the abutment faces25, 26 and the adjustable positioning elements 23, 24 can be constructedin such a way that in the coupled state of the mobile container 12 theyengage in one another by positive locking. As can be seen from FIG. 3,the mobile container 12 is supported with its lower end on a plate 27,which is connected to the mounting 13′ by springs and biased in such away that the mobile container 12 seen in FIG. 3 is pushed upwards insuch a way that the adjustable positioning elements 23, 24 are inengagement with the abutment faces 25, 26. The plate 27 is constructedin such a way that it has a recess 29 in the middle, through which thevertical drive 4 is guided. On the vertical drive 4 a carrier 30 ismounted, which, as shown in FIG. 3, is arranged above the plate 27. Thecarrier 30 is constructed in such a way that it is larger than therecess 29 of the plate 27. Therefore when the vertical drive 4 movesdownwards the carrier 30, as shown in FIG. 4, comes into contact withthe plate 27 and takes it with it in the movement downwards against theforce of the spring.

Further provided, as shown in FIG. 3, are two circulating chains 31, 32,arranged below the plate 27. On the underside of the projections 21, 22of the construction frame 1 in each case a chain coupling element 33, 34is mounted. The chains 31, 32 and the chain coupling elements 33, 34 arearranged with respect to one another in such a way that when theconstruction frame 1 moves downwards the chain coupling elements 33, 34come into contact with the chains 31, 32, as shown in FIG. 4.

The device further has another locking device 40, as shown in FIG. 6.FIG. 6 is a detail enlargement of area A from FIG. 3, wherein the plate27, the springs 28 and the carrier 30 are not drawn in. On the undersideof the construction platform 3 a connecting piece 41 is mounted, onwhich a rocker arm with a first leg 43 and a second leg 44, extendingperpendicular to it, is carried so as to be rotatable over theconnecting area of the two legs 43, 44 at the crossing point of thelongitudinal axes of the legs. The open end of the second leg 44 isrotatably connected to a locking rod 45, which is guided in a guide 46in such a way that the locking rod 45 in the inserted state of themobile container 12 can be moved forwards and backwards onlyperpendicular to the direction of movement of the vertical drive 4, asindicated by the double arrow A in FIG. 6. The guide 46 is connected tothe construction platform via a connecting element, not shown. The frontend 47 of the locking rod 45, pointing away from the open end of thesecond leg 44, is constructed as tapering. An annular recess 48, formedcorresponding to the front end 47 is provided on the vertical drive 4. Arotatably carried roller 49 is provided at the open end of the first leg43 of the rocker arm 42. In the position of the construction platform 3shown in FIG. 6 the roller 49 is in contact with an unlocking projection50 of the construction frame 1. Between the rocker arm 42 and theconnecting piece 41 is arranged a torsion spring 41, which biases therocker arm in such a way that the locking rod 45 is moved towards thevertical drive 4. The rocker arm 42, the unlocking projection 50 and thelocking rod 45 are arranged in such a way that on further movement ofthe vertical drive 4 downwards in the state shown in FIG. 6 theunlocking projection 50 presses the first leg 43 of the rocker arm 42via the roller 49 upwards against the force of the spring of the torsionspring 51, so the locking rod 45 in FIG. 6 is moved to the left, wherebythe engagement of the front end 47 with the recess 48 is released.

The operation of the device will now be described. It is therein assumedthat a construction platform 3 and a construction frame 1 are alreadycontained in the device or in the construction area. First theconstruction platform 3 is positioned in the construction frame 1 insuch a way that it is positioned below the upper edge 2 of theconstruction frame 1 by a predetermined layer thickness. Then by meansof the application device 8 a layer of the material to be hardened isapplied to the construction platform 3 and then selectively hardened atthe desired places with the hardening device. After that theconstruction platform is lowered by a desired layer thickness and afurther layer of material is applied. This is again selectively hardenedand therein connected to the lower layer of material. This is continueduntil the object to be manufactured is complete. Several objects insuccession and/or on top of one another on the construction platform 3can also be manufactured in a construction process of the sortdescribed. Then the construction platform 3 is moved into the positionshown in FIG. 3. The control system 9 controls the vertical drive 4further in such a way that it travels from the position shown in FIG. 3further downwards. In this way the carrier 30 comes into contact withthe plate 27 and takes it with it when the vertical drive movesdownwards against the force of the spring of the springs 28. In this waythe mobile container 12, which is located on the plate 27, is also moveddownwards. Thus the engagement between the adjustable positioningelements 23, 24 and the abutment faces 25, 26 is released. This movementof the vertical drive 4 downwards is continued until the chain couplingelements 33, 34 reach engagement with the chains 31, 32, as shown inFIG. 4. Simultaneously by this movement of the vertical drive 4downwards the first leg 43 of the rocker arm 42 is pressed against theunlocking projection 50 of the construction frame 1, shown in FIG. 6,whereby the first leg 43 is moved towards the construction platform. Inthis way the locking rod 45 seen in FIG. 6 is moved to the left and theengagement between the front end 47 of the locking rod 45 and the recess48 is released. Therefore the construction frame 1 is uncoupled from themounting 13′ and the construction platform 3 separated from the verticaldrive 4. Now by means of the control system 9 the automatic door 14(FIG. 2) is opened and the chains 31, 32 triggered, whereby the fullmobile container 12 is conveyed out of the device (FIG. 5). The switchgear 19 has previously been set in such a way that the full mobilecontainer 12 is conveyed to the removal section 17. From there the fullmobile container 12 is conveyed to the store. After that the switch gear19 is re-set in such a way that the feed section 16 is connected to theconnecting section 18. Via this connection an empty mobile container 12₁ is now conveyed into the machine. The vertical drive 4 is now movedupwards by the control system 9. In this way in reverse order the emptymobile container 12 ₁ is coupled to the mounting 13′ of the housing 13,as shown in FIG. 3, and the construction platform 3 is locked to thevertical drive 4, as shown in FIG. 6. The control system 9 now carriesout all the activities necessary for starting a new constructionprocess. This comprises, for example, providing the geometrical data forthe object to be manufactured and checking the state of the device. Thischecking comprises, for example, a check of whether there is stillsufficient material in the device and checking the hardening device.Based on the result of this checking, for example topping up materialfrom an external storage vessel, cleaning the hardening device and/orcarrying out a calibration of the hardening device are controlled by thecontrol system 9. After that the control system 9 starts a newconstruction process and a new object is now formed on the constructionplatform 3 of the empty mobile container 12 ₁. The steps described areall carried out automatically by means of the control system 9.

One advantage of this embodiment is that coupling and uncoupling of theconstruction frame 1 to the mounting 13′ of the housing 13 is carriedout by the movement of the vertical drive 4. This saves having anadditional actuator. Furthermore, the actuating force for the locking ofconstruction platform 3 and vertical drive 4 is also derived from themovement of the vertical drive 4. A solution of this kind has theadvantage, in view of the raised temperatures occurring in this area ofthe construction frame, typically between 100 and 150°, when certainmaterials are used, such as e.g. synthetic powder, that no actuator issubjected to these temperatures. In addition there is no need forsensors or switches, which promotes simplicity and thereforereliability.

In an alternative embodiment it is possible to generate the liftingmovement required for coupling the construction frame 1 to the mounting13′ of the housing 13 and for locking the construction platform 3 to thevertical drive 4 by an additional actuator. An additional actuator canalso be provided in each case for each of these movements.

In a further development of the invention the housing 13 of the devicebordering on the front side has a further door on one of the side wallsor on the back. The rail system is then connected to this door andprovided either at the side of or behind the machine. This has theadvantage that the machine can be loaded manually through the door 14 onthe front face and automatically via the rail system via the side orrear door. Also in a further development the control system isconstructed in such a way that after the manufactured object has beenremoved system maintenance of the device, comprising, for example,cleaning the blades of the application device, cleaning the optics ofthe laser system and/or re-calibration, is carried out automatically.

A device and a method have been described in which the object ismanufactured in layers by means of controlled action of a laser beam atpoints in each layer corresponding to the cross-section of the object.Devices and methods of this kind are, for example, a laser sinteringdevice or a stereolithography device and the associated methods. Theinvention is not, however, restricted to these. Any device and anymethod can be provided in which the object to be manufactured is formedgeneratively, i.e. the object is formed by controlled adding ofconstruction material. For example, a device can also be provided inwhich an object is manufactured by hardening in layers of a powderedmaterial by means of an adhesive.

A decisive point of the present invention is that the control system 9controls the manufacture of one or more objects, the unloading of thisor these object(s) from the construction area of the device, theexecution of the activities for a further construction process, formingone or more further objects, the unloading of this or these object(s),etc. in such a way that this is carried out fully automatically. In thisway a fully automatic sequence of several construction processes isenabled by generative manufacturing methods. Furthermore, no manualactivities are required and the productivity of the device or the methodis increased.

In the embodiments described loading the construction area of the devicewith an empty mobile container 12 ₁, 12 ₂, forming the object andunloading from the mobile container 12 ₃ with the object formed thereinfrom the construction area is controlled in such a way that it iscarried out automatically. It is also possible, however, for only theconstruction platform 3 to be replaced automatically. This isparticularly the case with the kind of devices for generativemanufacture or manufacture in layers of a three-dimensional object whichhave a construction frame rigidly connected to the machine or which haveno construction frame. A device without construction frame is, forexample, a device for the FDM method (FDM=fused deposition modelling),described for example in U.S. Pat. No. 5,121,329.

Furthermore, in a further embodiment it is also possible that only themanufactured object is unloaded from the construction area of the deviceand afterwards a further object is manufactured which is again unloaded.

Furthermore, on removal from the construction area the manufacturedobjects can be put into a different area of the device and later removedmanually or automatically from the device.

What is claimed is:
 1. A device for generative manufacture of athree-dimensional object, the device comprising: a construction area, inwhich the object is manufactured; a controller; a construction platform;a conveyor; a platform supplier, which feeds the construction platformto the conveying device; and a platform remover device, which removesthe construction platform from the device from the conveying deviceafter the object is manufactured; wherein the controller controls theexecution of the following steps: a) manufacture of an object; b)removal of the manufactured object from the construction area; and c)repeating steps a) and b); wherein at least step b) utilizes theconveyor, and wherein the platform supplier and platform remover areconnected to the conveying device by a switch gear.
 2. A device forgenerative manufacture of a three-dimensional object, the devicecomprising: a construction area, in which the object is manufactured; acontroller; a construction platform; a conveyor; a traveling actuator,which sets the position of the construction platform in the constructionarea; and a connector, which connects the construction platform to theactuator wherein the controller controls the execution of the followingsteps; a) manufacture of an object; b) removal of the manufacturedobject from the construction area; and c) repeating steps a) and b);wherein at least step b) utilizes the conveyor.
 3. The device accordingto claim 2, further comprising a connection final control element, whichactuates the connector.
 4. The device according to claim 3, wherein theconnection final control element is the actuator.
 5. The deviceaccording to claim 2, wherein the construction platform comprises theconnector.
 6. A device for generative manufacture of a three-dimensionalobject, the device comprising: a construction area, in which the objectis manufactured; a controller; a construction platform; a conveyor; anda construction frame, which surrounds the construction platform, andwhich is moved together with the construction platform wherein thecontroller controls the execution of the following steps: a) manufactureof an object; b) removal of the manufactured object from theconstruction area; and c) repeat steps a) and b); wherein at least stepb) utilizes the conveyor.
 7. The device according to claim 6, furthercomprising: a mounting; and a coupler, which joins the constructionframe to the mounting during loading and detaches the construction framefrom the mounting during unloading.
 8. The device according to claim 7,wherein the coupler comprises a coupling element, which joins theconstruction frame with the mounting.
 9. The device according to claim7, further comprising a coupling final control element for couplingand/or uncoupling.
 10. The device according to claim 7, wherein thecoupling final control element is the actuator.
 11. The device accordingto claim 9, wherein the coupler element is biased and the couplercomprises a carrier connected to the coupling final control element,wherein the carrier can be moved by the coupling final control elementto move the coupling element against the bias.
 12. The device accordingto claim 7, wherein the coupler comprises an adjustable positioningelement, with which the relative position of the construction frame tothe mounting in the coupled state can be set.
 13. A method forgenerative manufacture of a three-dimensional object with a device; themethod comprising the steps of: a) automatically loading of theconstruction area of the device with a construction platform forcarrying the object to be manufactured; b) manufacturing the object onthe construction platform in a construction area; c) automaticallyremoving the manufacture object from the construction area; d) repeatingsteps a), b) and c); wherein step a) further comprises connecting theconstruction platform to a traveling actuator for setting the positionof the construction platform in the construction area.
 14. A method forgenerative manufacture of a three-dimensional object with a device; themethod comprising the steps of; a) automatically loading of theconstruction area of the device with a construction platform forcarrying the object to be manufactured; b) manufacturing the object onthe construction platform in a construction area; c) automaticallyremoving the manufactured object from the construction area; and d)repeating steps a), b) and c): wherein step a) further comprisesautomatically loading the construction platform into the constructionarea with a construction frame surrounding the construction platform.15. The method according to claim 14, further comprising connecting theconstruction frame to a mounting of the device.
 16. The device accordingto claim 1, further comprising an applicator for supplying hardenablematerial on to the construction platform; and a hardening device, whichselectively hardens the material.
 17. The device according to claim 1,wherein the device is structured and arranged such that the object canbe manufactured in layers.
 18. The device according to claim 1, whereinthe controller is structured and arranged such that, after themanufactured object has been removed, a system maintenance of the deviceis carried out automatically.
 19. The device according to claim 2,further comprising an applicator for supplying hardenable material on tothe construction platform; and a hardening device, which selectivelyhardens the material.
 20. The device according to claim 2, wherein thedevice is structured and arranged such that the object can bemanufactured in layers.
 21. The device according to claim 2, wherein thecontroller is structured and arranged such that, after the manufacturedobject has been removed, a system maintenance of the device is carriedout automatically.
 22. The device according to claim 6, furthercomprising an applicator for supplying hardenable material on to theconstruction platform; and a hardening device, which selectively hardensthe material.
 23. The device according to claim 6, wherein the device isstructured and arranged such that the object can be manufactured inlayers.
 24. The device according to claim 6, wherein the controller isstructured and arranged such that, after the manufactured object hasbeen removed, a system maintenance of the device is carried outautomatically.
 25. The method according to claim 13, wherein the devicecomprises an applicator for supplying hardenable material onto theconstruction platform, and a hardening devices which selectively hardensthe material, and step b) further comprises: supplying hardenablematerial onto the construction platform; and selectively hardening thematerial.
 26. The method according to claim 13, wherein the device isstructured and arranged such that the object can be manufactured inlayers and the step b) further comprises manufacturing the object inlayers.
 27. The method according to claim 13, wherein the devicecomprises a controller that is structured and arranged such that, afterthe manufactured object has been removed, a system maintenance of thedevice is carried out automatically and step c) further comprisescarrying out automatically a system maintenace.
 28. The method accordingto claim 14, wherein the device comprises an applicator for supplyinghardenable material onto the construction platform, and a hardeningdevice, which selectively hardens the material, and step b) furthercomprises: supplying hardenable material onto the construction platform;and selectively hardening the material.
 29. The method according toclaim 14, wherein the device is structured and arranged such that theobject can be manufactured in layers and the stop b) further comprisesmanufacturing the object in layers.
 30. The method according to claim14, wherein the device comprises a controller that is structured andarranged such that, after the manufactured object has been removed, asystem maintenance of the device is carried out automatically and stepc) further comprises carrying out automatically a system maintenace.